<?php

/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Gdata
 * @subpackage Gdata
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: MediaMimeStream.php 16971 2009-07-22 18:05:45Z mikaelkael $
 */

/**
 *  @see Zend_Gdata_MimeFile
 */
require_once 'Zend/Gdata/MimeFile.php';

/**
 * @see Zend_Gdata_MimeBodyString
 */
require_once 'Zend/Gdata/MimeBodyString.php';


/**
 * A streaming Media MIME class that allows for buffered read operations.
 *
 * @category   Zend
 * @package    Zend_Gdata
 * @subpackage Gdata
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Gdata_MediaMimeStream
{

	/**
	 * A valid MIME boundary.
	 *
	 * @var string
	 */
	protected $_boundaryString = null;

	/**
	 * A handle to the file that is part of the message.
	 *
	 * @var resource
	 */
	protected $_fileHandle = null;

	/**
	 * The current part being read from.
	 * @var integer
	 */
	protected $_currentPart = 0;

	/**
	 * The size of the MIME message.
	 * @var integer
	 */
	protected $_totalSize = 0;

	/**
	 * An array of all the parts to be sent. Array members are either a
	 * MimeFile or a MimeBodyString object.
	 * @var array
	 */
	protected $_parts = null;

	/**
	 * Create a new MimeMediaStream object.
	 *
	 * @param string $xmlString The string corresponding to the XML section
	 *               of the message, typically an atom entry or feed.
	 * @param string $filePath The path to the file that constitutes the binary
	 *               part of the message.
	 * @param string $fileContentType The valid internet media type of the file.
	 * @throws Zend_Gdata_App_IOException If the file cannot be read or does
	 *         not exist. Also if mbstring.func_overload has been set > 1.
	 */
	public function __construct($xmlString = null, $filePath = null,
	$fileContentType = null)
	{
		if (!file_exists($filePath) || !is_readable($filePath)) {
			require_once 'Zend/Gdata/App/IOException.php';
			throw new Zend_Gdata_App_IOException('File to be uploaded at ' .
			$filePath . ' does not exist or is not readable.');
		}

		$this->_fileHandle = fopen($filePath, 'rb', TRUE);
		$this->_boundaryString = '=_' . md5(microtime(1) . rand(1,20));
		$entry = $this->wrapEntry($xmlString, $fileContentType);
		$closingBoundary = new Zend_Gdata_MimeBodyString("\r\n--{$this->_boundaryString}--\r\n");
		$file = new Zend_Gdata_MimeFile($this->_fileHandle);
		$this->_parts = array($entry, $file, $closingBoundary);

		$fileSize = filesize($filePath);
		$this->_totalSize = $entry->getSize() + $fileSize
		+ $closingBoundary->getSize();

	}

	/**
	 * Sandwiches the entry body into a MIME message
	 *
	 * @return void
	 */
	private function wrapEntry($entry, $fileMimeType)
	{
		$wrappedEntry = "--{$this->_boundaryString}\r\n";
		$wrappedEntry .= "Content-Type: application/atom+xml\r\n\r\n";
		$wrappedEntry .= $entry;
		$wrappedEntry .= "\r\n--{$this->_boundaryString}\r\n";
		$wrappedEntry .= "Content-Type: $fileMimeType\r\n\r\n";
		return new Zend_Gdata_MimeBodyString($wrappedEntry);
	}

	/**
	 * Read a specific chunk of the the MIME multipart message.
	 *
	 * @param integer $bufferSize The size of the chunk that is to be read,
	 *                            must be lower than MAX_BUFFER_SIZE.
	 * @return string A corresponding piece of the message. This could be
	 *                binary or regular text.
	 */
	public function read($bytesRequested)
	{
		if($this->_currentPart >= count($this->_parts)) {
			return FALSE;
		}

		$activePart = $this->_parts[$this->_currentPart];
		$buffer = $activePart->read($bytesRequested);

		while(strlen($buffer) < $bytesRequested) {
			$this->_currentPart += 1;
			$nextBuffer = $this->read($bytesRequested - strlen($buffer));
			if($nextBuffer === FALSE) {
				break;
			}
			$buffer .= $nextBuffer;
		}

		return $buffer;
	}

	/**
	 * Return the total size of the mime message.
	 *
	 * @return integer Total size of the message to be sent.
	 */
	public function getTotalSize()
	{
		return $this->_totalSize;
	}

	/**
	 * Close the internal file that we are streaming to the socket.
	 *
	 * @return void
	 */
	public function closeFileHandle()
	{
		if ($this->_fileHandle !== null) {
			fclose($this->_fileHandle);
		}
	}

	/**
	 * Return a Content-type header that includes the current boundary string.
	 *
	 * @return string A valid HTTP Content-Type header.
	 */
	public function getContentType()
	{
		return 'multipart/related;boundary="' .
		$this->_boundaryString . '"' . "\r\n";
	}

}
